Blockchain network is an Internet database characterized by decentralization, transparency, and synchronization of database records (i.e., a shared ledger) by all nodes.
In one example, a blockchain network consists of various nodes, each node holding a shared ledger. Data associated with blocks are chronologically recorded on the shared ledger (data associated with a block corresponds to a set of transactions for which consensus regarding legitimacy is reached by all nodes during a period of time). In other words, the shared ledger records a timed chain of blocks of data, hence named “blockchain.” Each node may synchronize the shared ledger and validate the authenticity of each transaction.
In addition, any node has a right to suggest addition of a block of data to the shared ledger. All nodes may reach consensus regarding whether transactions corresponding to the block of data suggested to be added is legitimate, and add the block of data for which a consensus regarding legitimacy is reached into the shared ledger. There are mainly two types of blockchain networks now: public blockchain networks and consortium blockchain networks.
A public blockchain network is completely decentralized and transparent to the public. Any entity (individual or organization) may become a node in the public blockchain network and participate in transaction validation associated with the public blockchain network, which means that any entity may hold the shared ledger by becoming a node and request all nodes to reach a consensus on a block of data and record the block of data on the shared ledger.
However, since any entity may become a node in a public blockchain network, a hacker may easily intrude into the public blockchain network and attempt to control a majority of the nodes, add illegitimate blocks of data to the public blockchain (i.e., the shared ledger), and pose a threat to the security of the public blockchain network. In addition, any entity may view all transaction data stored on the public chain, while the transaction data often involve privacy of the node and non-node entities. Even if the transaction data is encrypted, there is still a risk for the encryption to be cracked.
A consortium blockchain network is partially decentralized and is not open to the public. Only a pre-designated entity may become a node in the consortium blockchain network, while other entities are not qualified to become nodes, nor can they hold the shared ledger or participate in consensus. The consortium blockchain network may provide services to entities outside the consortium blockchain network (non-node entities). A non-node entity may interface with the consortium blockchain network and request the consortium blockchain network to reach a consensus regarding legitimacy of a transaction generated by the non-node entity.
One consortium blockchain network often only relates to one transaction field. Nodes in a consortium blockchain network are often authoritative institutions in the field. For example, nodes in a consortium blockchain network in the financial field are often big banks and financial regulatory institutions. In addition, nodes in consortium blockchain networks for many transaction fields, such as bills, logistics, healthcare, government and administration, are also authoritative institutions in corresponding fields, respectively. Such characteristic of the consortium blockchain network gives hackers no opportunity to participate in consensus validation or to view transaction data stored on the consortium blockchain. This way, the security of the blockchain network is greatly improved. However, since nodes in a consortium blockchain network are often authoritative institutions in a transaction field, the consortium blockchain network can only provide public validation services in the particular transaction field. A non-node entity often needs to spend a very high cost to interface with consortium blockchain networks in different transaction fields, which is very inconvenient.
A non-node entity needs to select a corresponding consortium blockchain network according to a transaction field to which a transaction generated by the non-node entity belongs. Only after the non-node entity interfaces with a consortium blockchain network, can the non-node entity enjoy services provided by the consortium blockchain network. However, consortium blockchain networks may have different interfacing protocols. If a plurality of transactions generated by the non-node entity belong to different transaction fields, the non-node entity has to interface with a plurality of consortium blockchain networks according to different interfacing protocols, respectively, which is not convenient for the non-node entity.